Cybersecurity & Data Privacy and White Collar Defense & Government Investigations


Guillermo Christensen is a partner in the White Collar Defense & Government Investigation Group and Chair of the Cybersecurity and Data Privacy Practice at Brown Rudnick.   Guillermo advises multinational corporate clients on various enterprise risks involving information systems security and data security ("cybersecurity") and insider threats to corporate systems. He has conducted confidential internal investigations relating to cybersecurity incidents, allegations of foreign corruption, and violations of export controls and economic sanctions.  Guillermo regularly represents clients seeking to secure approvals from the Committee on Foreign Investment in the U.S. (CFIUS) for acquisitions of U.S. businesses by foreign buyers involving national security issues.  In all these areas, Guillermo brings a wealth of international business, intelligence, and national security experience to his practices and provides his clients with broader perspectives for troubleshooting complex and unusual problems.

In the government, Guillermo was a CIA intelligence officer and a diplomat with the U.S. State Department.  From 2001 to 2002, he was also the CIA Fellow to the Council on Foreign Relations in New York, an intelligence community position designated for officers on the cusp of the most senior responsibilities.  From 2002 to 2004, Guillermo was on loan from the CIA to the FBI and to a national counterterrorism fusion center to help improve intelligence collection and analysis of emerging threats.  He most recently served in a policy role as the Science and Technology Advisor to the U.S. Mission to the Organization for Economic Cooperation and Development (OECD) in Paris, where he led multi-stakeholder policy reviews of encryption, cybersecurity and cross-border data flows. 

In private practice, Guillermo has worked on a variety of complex international matters—including FCPA and OFAC investigation and dual use and high-technology exports. He has served clients across the financial, technology, energy and defense sectors, and has worked on matters in the Middle East, Latin America, Asia, Europe and Africa.

In the cybersecurity field, Guillermo is a thought leader on the topics of intelligence collection, counter-measures, business opportunities for emerging companies, and corporate governance.  Building upon his experience in the intelligence and national security realms his focus is on helping clients integrate information and network security practices into their enterprise risk process, and facilitating companies’ adaptation to technical and human (insider) threats and system vulnerabilities.  When breaches or insider threats are suspected, Guillermo leads Brown Rudnick’s multidisciplinary team to carry out investigations, manage crises, and assist clients in the remediation process.  Guillermo also frequently speaks on cybersecurity topics to audiences nationwide – he is currently involved in drafting a Sedona Conference Working Group 11 project on data security for law firms. 

Guillermo is active with several prominent organizations including as a life member of the Council on Foreign Relations, where he serves on the selection committee for the International Affairs Fellowship.  He also serves on the Advisory Board of the Reves Center for International Studies at the College of William and Mary. He was a 2016 Fellow of the Leadership Council on Legal Diversity (LCLD).   


Cybersecurity and Data Privacy

Assisted client with ransomware attacks on “family jewel” type assets

Negotiated with the U.S. Government following a breach in a sensitive defense related contract

Counseled client in managing ransomware incident and insurance claims

Counseled a client after key systems were hijacked by hackers and posed a mission critical threat to their systems. Assisted the client in securing and recovering their assets

Trained energy clients at the staff and management level on assessing and scoping cybersecurity threats

Advised clients on intellectual property-related matters involving information security and associated systems

Counseled on cybersecurity dimensions of M&A transactions

Corporate Investigations and FCPA Compliance

Conducted a year-long internal investigation for a Fortune 100 high technology company in South America and Europe

Conducted an internal investigation in Colombia for a Fortune 100 company involving hiring practices and government officials

Conducted internal investigations and performed risk assessments relating to FCPA compliance, among the locations involved are Myanmar/Burma, Brunei, Chad, Saudi Arabia, Equatorial Guinea, Angola, Singapore, China, Russia, the UAE, Thailand, Malaysia, Mexico, Iraq, Egypt, Colombia and the UK

Fortune 500 oil services company – conducted acquisition due diligence on corporate target and post-closing diligence

Fortune 1000 company – consulted on enhancements to global anticorruption policies and procedures and training program

Russian telecommunications company – due diligence review in connection with planned acquisition of telecommunications company

Oil services company – drafted anticorruption policies and associated procedures and provided training to board, senior management and sales teams

Regulatory and National Security Law

Secured regulatory approvals including CFIUS for transaction involving weapons manufacturer

Led global information and communications technology (ICT) solutions provider – advice and representation before CFIUS in connection with proposed U.S. investment activities

U.S. aviation maintenance and repair company – representation before CFIUS, State Department and Defense Security Service in connection with acquisition by AsiaPac purchaser

Secured CFIUS clearance by European aerospace company in a $1 billion acquisition of commercial and military aircraft business

International oilfield services company – comprehensive audit of export controls and sanctions compliance programs in connection with U.S. government investigation

Various multinational companies – regularly developed and oversaw implementation of global export control and sanctions compliance programs

Large U.S. chemicals company – conducted comprehensive review of technology at all U.S. facilities to assess compliance with U.S. technology “deemed export” controls

International energy companies – advised on compliance with Crimea and Ukraine sanctions

Middle Eastern companies – counseled on compliance with U.S. Iran and Syria sanctions

International Arbitration and Complex Business Litigation

Sovereign state – arbitration of initial claims under a joint dispute board arising from a hydropower project

Represented the deposed head of a democratically elected government on a range of international legal matters

Represented petitioner before U.S. Supreme Court on statute of limitations appeal (BP Am. Prod. Co. v. Burton, 549 U.S. 84 (2006))


Georgetown University Law Center – J.D., cum laude, 2005
Georgetown University – M.S., Foreign Service, 1990
American University – B.A., International Relations, 1988

Bar Admissions

District of Columbia
New York
Speaking Engagements
Professional Affiliations
Community Involvement
Media Coverage